Burglar-alarm lock.



A. F. W. VIEHWEGER.

BURGLAR ALARM LOCK.

APPLICATION FILED APR. 7. 191a.

Patented Sept. 26, 1916.

2 SHEETSSHEET 1.

WHY. e99! MM A. F. W. VIEHWEGER.

BURGLAR ALARM LOCK.

APPLICATION FILED APR- 7. 1916.

1 ,1 99,638. Patented Sept. 26, 1916.

2 SHEETSSHEET 2.

AUGUST F. W. VIEHWEGER, OF HOBOKEN, NEW J ERSEY.

BURGLAB-ALARM LOCK.

Specification of Letters Patent.

Patented Sept. 26,1916.

Application filed April 7, 1916. Serial No. 89,607.

To all whom it may concern:

Be it known that I, AUGUST F. W. VIEH- WEGER, a subject of the Emperorof German residing at Hoboken, in the county of udson and State of NewJersey, have invented certain new and useful Improvements inBurglar-Alarm Locks; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

The invention relates to a combined lock and burglar alarm.

The object of the present invention is to provide a simple, practicaland comparatively inexpensive combined burglar alarm and lock adapted tobe readily applied to doors and capable when set of enabling the door tobe opened by a. proper key without sounding the alarm and adapted alsoshould an attempt be made to open the lock with a false key or to pickthe lock to sound a burglar alarm and continuously operate the same.

A further object of the invention is to provide a device of thischaracter adapted to be readily applied to various kinds of door locksfor rendering the same burglar proof and for sounding an audible alarmin event of an attempt to pick the lock.

With these and other objectsin view, the invention consists in theconstruction and novel combination of parts hereinafter fully described,illustrated in the accompanying drawings, and pointed out in the claimshereto appended; it being understood that various changes in the form,proportion, size and minor details of construction, within the scope ofthe claims, may be resorted to without departing from the spirit orsacrificing any of the advantages of the invention.

In the drawings Figure 1 is a perspective view of a door lockconstructed in accordance with this invention and arranged in circuitwith a burglar alarm, Fig. 2 is a vertical longitudinal sectional viewthrough the lock, Fig. 3 is a transverse sectional view on the line 3-3of Fig. 2, Figs. 4 and 5 are detail erspective views of the latch bolt,Fig. 6 1s a detail view of the hub member of the knob for actuating thebolt from the interior, Fig. 7, is a detail perspective view of theslidable contact member, Fig. 8 is a detail view of the key.

construction is preferably provided with a removable face plate 4 havinga flange 5 designed to be arranged in a suitable mortise or recess atthe edge of the door. The bolt is provided at its rear portion with alongitudinal slot 5 in which extends a horizontally disposed supportingand guiding arm 6 having an attaching portion 7 which is suitablysecured to the rear wall of the lock casing as clearly illustrated inFig. 2 i

of the drawings. The bolt is provided at the inner side with upper andlower shoul ders 8 which are adapted to be engaged by a hub member 9pivoted intermediate of .its ends to a spindle 10 of a knob 11 locatedat the inner face of the door, not shown, and adapted to be turned tocause the hub member to engage one or the other of the upper and lowershoulders 8 for retracting the slidable bolt 1 against the action of acoiled spring 12. The coiled spring 12 which is secured at its rear endto the upper portion of the lock casing is connected at its forward endto the up er arm of an inclined lever 13 fulcrumed intermediate of itsends on a pivot 14 and having in its lower arm a slot 15 for thereception of a suitable pivot 16 that is carried by the bolt. The pivot16 which may consist of a screw is mounted in an opening 17 of theslidable bolt which is normally maintained in an extended position bythe spring 12. The pivot 14 of the lever 13 has also mounted on it acatch 18 extending upwardly and forwardly from the pivot 14 andconsisting of an arm provided with a lower engaging portion or tooth 19and normally su ported in an elevated position with the said tooth 19out of engagement with a recess 20 of the bolt by a leaf spring or platespring 21. The spring 21 is secured at its rear end to the upper wall ofthe lock casing and the forward end is connected with the front portionof the arm of the catch as clearly illustrated in Fig. 4 of thedrawings.

The catch may consist of a single piece of sheet metal bentv to form thetooth or engaging portion and a flange 22 which engages the front end ofthe spring 21. The

notch or recess 20 is formed in the upper edge of the slidable bolt atthe front portion thereof and it is located below the tooth or engagingportion of the catch when the bolt is in its extended position. Thecatch is adapted to be depressed and maintained in engagement with therecess 20 by an operating device 23.

The operating device 23 consists of a head and a stem 24 provided withprojecting lugs 25 adapted to extend through slots 26 in the top wall ofthe casing so that the operating device 23 may be depressed andpartially rotated to force the catch into engagement with the latch boltand lock the catch in such engagement. This will efi'ectually preventthe bolt from being retracted or operated from the exterior.

The slidable bolt is provided in its lower portion with a recess 27forming a shoulder 28"and adapted to receive the engaging portions 29 ofa key 30 for enabling the key to engage the shoulder 28 and retract thebolt. The key is provided with spaced bits 31 which may be arranged in avariety of ways which are also adapted to pass through recesses 32 of aslidable contact member 33 preferably consisting of an arched piece ofmetal which is connected at a point intermediate of its ends to a stemor shank 34 of a knob 35. The stem or shank 34 extends through a slot 36in the lower wall of the latch casing and it is adapted to be engaged bya key and to be moved into electrical engagement or contact with a fixedcontact member 37. The lock casing is provided at the outer side with akey hole 38 for the introduction of a key in the usual manner and anyattempt to pick the lock with an ordinary key or pick will result inmoving the contact member 33 into engagement with the contact member 37.This will operate to ring an electric bell 38 which may be mounted onthe door or at any other convenient ploint and which is arranged incircuit wit the contact members when the same are in engagement witheach other. The contact member 37 is mounted on the stem or screw 39 ofa binding post 40 to which one of the conductor wires 41 of the electriccircuit is connected. The wire 41 preferably extends to a suitablesource of electric current supply 42 which may consist of one or morebatteries or any other suitable means. The source of current supply isconnected with the electric bell by a conductor wire 43 and the electricbell is also connected with ii binding 0st 44 by a conductor wire 45.The binding post is mounted on the lock casing and the contact member 37is insulated from the lock casing and it will be clear that when theslidable contact member 33 is carried by a key or pick into engagementwith the fixed contact member 37, the circuit will be closed and thebell continuously sounded until the circuit is again opened by movingthe slidable contact member away from the relatively fixed contactmember 37 Any other suitable alarm or signal may be arranged in circuitwith the bell as will be readily understood and the fixed and movablecontact with the electrical connection may be applied to various formsof locks with the movable contact arranged in the path of the key or inthe circle described by the'bits of the key so that when a proper key isnot used and attempt is made to surreptitiously open the door to whichthe lock is applied the circuit will be closed. It will be seen that thecharacter of the key and the construction of the adjacent end of themovable contact member may be correspondingly varied.

No claim is made in the present application to the lock structure, asthis forms the subject matter of a separate application.

What is claimed is 1. A look including a key actuated bolt, a fixedcontact member carried by the lock, a

movable contact member mounted in the lock and extending into the aredescribed by the key and having an opening or cut away portion to permitthe passage of a proper key without actuating the movable contact memberand adapted to be moved into engagement with the fixed contact by animproper key or device for closing an electric circuit, and anexteriorly arranged operating device connected with the movable memberfor moving the same away from said fixed contact member, said movabletending into the path or are of movement of the key of the lock andadapted to permit the passage of the same and to be actuated by animproper key or instrument so as to be moved into contact with the fixedcontact member and an operating device having a shank or portionextendlng into the lock from the exterior thereof and connected with theslidable contact member for moving the same away from the fixed contact13 member.

In testimony whereof I aflix my signature in presence of two Witnesses.

AUGUST F W. VIEHWEGER.

Witnesses: V

' CHARLES FAIsT, OTTO Gi'm'rnnn.

